knight



(No Model.)

w H KNIGHT BACK AND GEAR FOR INGLINED RAILWAYS.

Patented Mar. 26, 1889..v

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UNITED STATES.

PATENT OFFICE.

WALTER H. KNIGHT, OF NEWV YORK, N. Y.

RACK AND GEAR F OR lNCLlNED RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 400,347, dated March 26, 1889.

. Application filed October 16, 1888. Serial No. 288,243. (No model.)

To all whom it may concern.-

Be it known that I, WALTER H. KNIGHT, a citizen of the United States, residing at New York, in the county of New York, State of New York, have invented certain new and useful Improvementsin Racks and Gears for Inelined Railways, of which the following is a specification.

My invention relates to railways con itructed on a grade, where it is essential to provide a rack on the roadway engaging with a gearwheel on the car. In constructing a road of this character I have found it necessary to provide, first, a perfect alignment between rack and rail in order that the gear-wheel may at all times properly engage, with the rack. For this reason I construct my rack-rail separately from the bearing-rail and bolt or rivet the two together; second, I have found that when the rack-rail and bearing-rail are thus secured together it is essential that the rackrail be on the outside, in order that the gearwheel may not interfere with the guard-rails on curves and switches; third, the above-described arrangement permits the gear-wheel and the driving-wheel to be attached together, obviating the necessity of an independent gear-wheel with clutches or other apparatus for bringing it into engagement with the rack; fourth, in the above-described construction it follows that the pitch-circle of the gear-wheel must coincide with the tread of the drivingwheel, in order that both may advance at the same rate of speed. If, under these conditions, the teeth of the gear-wheel were formed in the ordinary manner to satisfy the theoretical conditions of a gear engaging with a rack, the teeth would project a certain distance beyond the pitch-circle, thus forming an objectionable feature on curves and where the wheel is adapted to run on parts of the roadway where there is no rack. I thereforev cut off the gear-teeth at the pitch-circle, having found from experience that for practical work upon a roadway atooth thus constructed will be perfect enough to perform successfully its function of preventing slippage of the driving-wheel.

In the accompanying drawings I have illustrated my invention, Figure I being a side sisting in the present instance of a tongue, 0,

upon the gear engaginga corresponding groove in the driver. In this way the screws 0 are relieved from strain.

D is the pitch-circle of the gearwheel, which coincides with the tread of wheel A. I have shown in dotted lines the outline of the ordinary tooth usually employed when a gear-Wheel engages with a rack. In this case, however, all the part of the tooth inclosed by the dotted lines has been cut away, so that each tooth terminates at the pitch-circle. By

this arrangement there is no extension of the teeth on the outside of the rail below the tread, which would interfere with the progress of the wheel along parts of the road not provided with a rack, and also with the operation of the wheel upon a curve. This also permits of a shorter tooth in the rack, as it is not necessary to provide the full depth of opening between the rackteeth, which would be necessary in case a perfect gear was employed. On this account the rack-teeth are much stronger and better adapted for the ,hard usage they receive on a traveled roadway.

E represents the rack, made in sections and bolted securely to the outside of the bearingrail F, the sections terminating, as shown in Fig. 1, at a point between two successive teeth. It will be seen that the rail F is of the girder type, having an upright contracted web, with the lower flange for a base and an upper flange forming the bearing-head of the rail. The rack-rail has a continuous bearing upon the track-rail, and as it is bolted directly thereto the relative position of the rails is maintained constant, thereby insuring the proper working of the gearing. 'Moreover, the collection of dirt or stones between the two rails is avoided by shaping them so as to fit each other snugly. The rack E is preferably made a casting of iron or steel, and at its lower part it has an offset fitting into the middle part of the rail F, while strength is given to it by brackets G, placed at intervals. The rack and rail thus formed have the advantage of presenting no obstruction or unsightly appearance when laid in a street. The rack can also be placed only at intervals along a line where it is necessitated by the grades. The gear-wheel will automatically engage with the rack as it goes along, and forms no obstruction to the wheel upon other parts of the road. In racks heretofore used it has been customary to provide a special shaft or axle carrying the gear-wheel, which may be raised or lowered into engagement with a rack placed in the center of the track and of a construction which would prevent its being used upon a traveled street.

Having thus fully set forth my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The combination, with the driving-wheel of a vehicle, of a gear-wheel having its pitchcirele substantially coincident with the tread of the wheel, and teeth terminating substantially at the pitch-circle.

3. The combination, with the bearing-rail of a railway, of a rack thereon having its teeth projecting above the tread of the rail, and a driving-wheel on a vehicle provided with a gear whose pitch-circle is substantially coincident with the tread of the wheel and whose teeth terminate at the pitch-circle.

3. The combination, with the bearing-rail of a railway, of an outside rack attached thereto and a driving-wheel of a vehicle having a gear on the outside adapted to engage with the said rack, the said gear having its pitch-circle substantially coincident with the treadof the wheel and its teeth terminating at the pitelreircle.

at. The combination, with the bearing-rail of a railway, of a sectional rack-rail attached thereto, the sections of the rack terminating at a point between two adjacent teeth.

5. The combination, with a girder-railon a railway having a contracted upright web, of a rack-rail fitted to the web of the said girderrail and attached thereto, substantially as described.

6. The combination of a bearing-rail of a railway having a single contracted web,with a rack-rail fitted thereto, and fastening devices for the rack-rail passing through the web of the bearing-rail.

7. The combination of a bearing-rail of a railway having a contracted web and broadened bearing-flanges, with a rack-rail fitted thereto and having a substantially continuous bearing upon the bottom flange of said track-rail.

8. The combination of a bearing-rail of a railway with a rack-rail having a bearing by its under face on the track-rail, and fastening devices securing the rack-rail to the web of the track-rail, as set forth.

9. The combination, with the bearing-rail of a railway having a contracted web and broadened bearing-surface, of a separatelyformed rack shaped to fit the said rail, and fastenings holding the rack in place.

10. The combination, with a bearing-rail of a railway, of a separately-formed rack-rail secured in place by the side of the bearing-rail and having strengthening-ribs at intervals.

11. The combination, with a rack by the side of a railway-track rail, of a gear, fastenings securing the gear to the driving-wheel of the vehicle, and suitable intermediate stops holding the two wheels in place and thereby relieving the fastenings from strain.

WALTER IT. KNIGI-ll. itnesses:

C. 0. Citrus, Rom. W. BLAcKWELL. 

